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really, they use a cotton candy machine?

Electron microscope image of polymer channels made with a cotton candy machine

Scientists at Vanderbilt University have discovered a new use for the machine that is used to make cotton candy. Cotton candy is basically sugar that is spun into thin fibers. The cotton candy machine was invented by William Morrison a dentist in collaboration with a candy maker John Wharton. Instead of using sugar, these scientists used a polymer to make a network of thin threads. The threads serve to create tiny channels in gelatin and the polymer is removed leaving just the tiny channels. The channels range in size from a few thousand nanometers to almost 100,000 nanometers. The structures they make are used to study how oxygen and nutrients are transported through tissues by tiny blood vessels. For a video describing the science go to the National Science Foundation